iPhone Straight Talk Data Suddenly Broken?

Recently the Straight Talk data plan that I use on my iPhone 4 with iOS 5.1.1 suddenly stopped working. Here’s how I fixed it:
My phone is jailbroken, and I use the TetherMe app from Cydia to manually add my data network settings. If you use TetherMe, you can simply add the settings as shown above by navigating to Settings->General->Network->Cellular Data Network. You’ll need to either reboot, or cycle Airplane Mode on and off for the settings to update. (I got these settings by searching this Straight Talk support page and searching under phone type ‘Other.’)

APN Settings

FIELD

SETTINGS

NAME

STRAIGHT_TALK

APN

tfdata

MMSC

http://mms-tf.net

MMS PROXY

mms3.tracfone.com

MMS PORT

80

MMS_APN

tfdata

Alternatively, you can use the APN installer from http://unlockit.co.nz if your phone is not jailbroken. Navigate to Create APN, and set your carrier to Straight Talk (New). Follow the prompts and you should be good to go.
*note: I use an AT&T sim card in my phone; not sure how this will behave with other flavors, e.g. Tmobil.